This relates generally to the field of depth buffering and, in particular, embodiments relating to techniques for improved depth buffering for graphics rendering in the creation of three dimensional graphics.
Computer graphic systems are used to model a scene having three dimensional objects and then to display them on two dimensional display devices. One such system in common use is a polygon-based, object-ordered graphics system in which three dimensional objects in a scene are each represented by a multitude of polygons that approximate the shapes of objects depicted in the image. Depending upon the orientation selected for viewing the scene in two dimensions, many of the primitives representing objects in a scene will be hidden behind other primitives and not displayed. Primitives not completely hidden are termed visible and will be displayed, either in full or in part, depending upon whether a portion of a given primitive is hidden in the rendered image of the display device. As the depth complexity of a scene to be rendered increases, the percentage of all primitives representing the scene that ultimately are visible by an observer of the display device decreases significantly. Thus, in many cases, many of the primitives for a scene will be hidden.